Release: Update version.

Author: =

docs/changelog.md

@@ -2,6 +2,10 @@
 
 This project uses semantic versioning and follows [keep a changelog](https://keepachangelog.com).
 
+## 4.0.1 -- 2025-08-08
+### Fixed
+- KeyError when not including all layers with regexes in a Layer rule.
+
 ## 4.0.0 -- 2024-04-01
 ### Changed
 - Mechanism of exporting library modules

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "PyTestArch"
-version = "4.0.0"
+version = "4.0.1"
 requires-python = ">=3.9"
 description = "Test framework for software architecture based on imports between modules"
 authors = [{ name = "zyskarch", email = "zyskarch@gmail.com" }]